+# RHEL >= 7 comes with systemd
+%if 0%{?rhel} >= 7
+%define with_systemd 1
+%endif
+
+# Fedora >= 15 comes with systemd, but only >= 18 has
+# the proper macros
+%if 0%{?fedora} >= 18
+%define with_systemd 1
+%endif
+
+# opensuse >= 12.1 comes with systemd, but only >= 13.1
+# has the proper macros
+%if 0%{?suse_version} >= 1310
+%define with_systemd 1
+%endif
+